The present invention relates generally to liquid conductivity monitoring devices, and more particularly to devices which provide an output indication upon the conductivity of a monitored liquid exceeding a predetermined threshold level.
It is frequently necessary to monitor on a continuous basis the purity of water and other liquids. In the case of water, this is typically accomplished by monitoring electrical conductivity, since conductivity is proportional to the quantity of ionizable dissolved solids, which in turn is a function of the impurity content of the water.
Applications which require continuous real-time monitoring of water purity include monitoring the output of a deionization chamber, such as that used to purify water, and monitoring the water circulating through a boiler to prevent damage and encrustation of the boiler tubes by unpure water. Also, it is frequently necessary to monitor natural water sources, such as rivers, lakes, etc. for pollution.
In the laboratory, the measurement of water conductivity can be made with great accuracy and methods and apparatus for doing so have achieved a high degree of refinement. Unfortunately, the apparatus and methods utilized in the laboratory do not, as a practical matter, lend themselves to on-site monitoring wherein unambiguous pure (or acceptable) and unpure (or unacceptable) indications are required on a continuous basis, without any manipulation or calculation on the part of the observer.
One form of prior-art on-site water conductivity monitoring device provided a light output indication to indicate a sufficient level of purity. However, this device provided no light indication during an unpure or unacceptable condition, and thus in the absence of an indication an observer could not readily ascertain whether the water was unacceptable or the monitoring device was unpowered or inoperative. Accordingly, the need has existed for a water conductivity monitoring device which provides light output indications of both pure and unpure states, on a continuous and unambiguous basis. The monitoring device of the present invention provides such indications, and is compact and economical to construct, so as to readily lend itself to a wide variety of on-site monitoring applications.
Accordingly, it is a general object of the present invention to provide a new and improved liquid conductivity monitoring device.
It is a more specific object of the present invention to provide a liquid conductivity monitoring device which provides continuous unambiguous output indications of pure and unpure liquid states.
It is a further object of the present invention to provide a new and improved liquid conductivity monitoring device which is simple and compact in construction, and can be readily installed in-line in liquid flow systems.